Various types of ovens are used for cooking food product. Rotisserie ovens are commonly used in the retail environment to cook chickens and other food products in a manner that permits store customers to view the food product during cooking. Rotisserie style cooking tends to result in grease, juices and food particles within the oven that require the oven to be cleaned regularly. Many commercial ovens use fans to circulate heated air through the cooking cavity. During operation various vapors/liquids can migrate up the fan drive shaft, which may negatively impact motor life. The addition of a cleaning cycle using liquids increases the potential for problems. It would be desirable to provide an oven with a suitable fan shaft arrangement that limits moisture migration to the fan motor.